Report highlights prevalence of mental illness in U.S.

One in five American adults ages 18 and older, or 45.6 million people, had mental illness in the past year, according to a report from the Substance Abuse and Mental Health Services Administration.

The "2011 National Survey on Drug Use and Health: Mental Health Findings" report presents results pertaining to mental health from the 2011 NSDUH, the primary source of statistical information on the use of illegal drugs, alcohol and tobacco by the civilian, noninstitutionalized population of the United States ages 12 years and older. Conducted by the federal government since 1971, the survey collects data through face-to-face interviews with approximately 65,750 people nationwide at the respondentís place of residence.

The rate of mental illness was more than twice as high among those 18 to 25 (29.8%) as among those 50 and older (14.3%), according to the report. Adult women were more likely than men to have had mental illness in the past year (23% vs. 15.9%).

Mental illness among adults ages 18 and older is defined as having had a diagnosable mental, behavioral or emotional disorder (excluding developmental and substance use disorders) in the past year, based on criteria specified in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychiatric Association.

The 2011 NSDUH also shows that 11.5 million adults (5% of the adult population) had serious mental illness in the past year. Serious mental illness is defined as mental illness that resulted in serious functional impairment, which substantially interfered with or limited one or more major life activities.

The rates of mental illness remained stable between 2010 and 2011.

"Although mental illness remains a serious public health issue, increasingly we know that people who experience it can be successfully treated and can live full, productive lives," SAMHSA Administrator Pamela S. Hyde said in a news release. "Like other medical conditions, such as cardiovascular disease or diabetes, the key to recovery is identifying the problem and taking active measures to treat it as soon as possible."

Among adults with mental illness in the past year, 38.2% received mental health services during that period. Among those who had serious mental illness in the past year, the rate of treatment was notably higher, 59.6%.

The report also notes that an estimated 8.5 million American adults (3.7%) had serious thoughts of suicide in the past year. Among that group, 2.4 million (1%) made suicide plans and 1.1 million (0.5%) attempted suicide. (Those in crisis or who know someone they believe may be at immediate risk of attempting suicide are urged to call the National Suicide Prevention Lifeline at 1-800-273-TALK or go to www.suicidepreventionlifeline.org. The Suicide Prevention Lifeline network, funded by SAMHSA, provides immediate, free and confidential crisis counseling to anyone in need throughout the country, around the clock and every day of the year.)

Adults who had mental illness during the past year were more than three times as likely to have met the criteria for substance dependence or abuse in that period compared with those who had not experienced mental illness during the past year (17.5% vs. 5.8%). Those who had serious mental illness during the past year were even more likely to have had substance dependence or abuse (22.6%).

The report also includes data regarding mental health issues among those ages 12 to 17. According to the report, 2 million youth in that age group (8.2% of this population) had experienced a major depressive episode in the past year. A major depressive episode is defined as a period of at least two weeks when a person experienced a depressed mood or loss of interest or pleasure in daily activities and had at least four of seven additional symptoms reflecting the criteria described in the Diagnostic and Statistical Manual of Mental Disorders.

Young people ages 12 to 17 who experienced a major depressive episode in the past year have more than twice the rate of past-year illicit drug use (36%) compared with their counterparts who had not experienced a major depressive episode during that period (17.4%).